Just a decade ago, if you wanted some bird seed, you probably picked up a bag at the neighborhood hardware store. Then you tossed the kernels on the ground or filled an inexpensive little plastic feeder stuck on a stake.

Today the chic avian fancier uses just the right kind of high-quality bird seed that is sure to lure even the fussiest feathered gourmand.

What's more, the seed often is poured into a beautifully designed $100 bird feeder made of galvanized steel or rough-hewn cedar, and guaranteed to last a lifetime.

Such accoutrements all are a part of one of America's fastest-growing trends: back-yard bird feeding.

Retailers and wildlife experts say it is an especially popular pastime with suburbanites seeking a connection to nature.

And when just two bird fanciers get together, they can talk at length about the relative merits of different kinds of bird seed and the myriad ways to foil squirrels bent on snatching seed. Further, bird fanciers proudly list the kinds of birds that visit their back-yard feeders as if they were counting precious pearls.

Riverwoods, Ill., resident and Lake County commissioner Martha Marks fondly talks about "her" red-bellied woodpecker that forages at a feeder just outside a window. Marks has three bird feeders, each adorned with suet in addition to seed, and has stocked up on 100 pounds of sunflower seed for the winter.

Marks is planning her next bird paraphernalia purchase, a platform feeder sold by a local emporium. The advantage of a platform feeder is that it caters to ground-feeding birds, such as juncos, that may have trouble feasting from other types of devices. It is constructed in such a way that the seed is kept off the ground and protected from damaging moisture. The trick, by the way, to keeping squirrels from a ground feeder, bird experts say, is to use safflower seed. The squirrels don't like it.

Catering to this hobby are a growing number of bird accessory boutiques. These small specialty stores supply bird seeds and supplies, from birdbath water heaters for frozen nights to bird videos and tapes of bird songs.

In 1991, no fewer than 63.1 million people fed birds in their back yards, according to the U.S. Fish and Wildlife Service.

In addition, $2 billion was spent on bird seed alone, a figure that does not include money spent on bird feeders and other equipment.

Comparison figures for previous years are not available, but the owner of a national chain of bird accessory stores estimates that business has quadrupled in the last decade.

Back-yard birders can increase their own awareness of wildlife and help researchers track bird populations throughout North America.

"Bird feeding has come of age," says Jim Carpenter, president of Wild Birds Unlimited Inc., a national franchise of bird specialty stores.

Carpenter opened his first store in Indianapolis in 1981, and today there are 157 stores throughout the U.S. and Canada.

The popularity of back-yard bird feeding is a natural extension of the interest in gardening and landscaping, says Phillip Habler, owner of Upstart Crow in Evanston, Ill.

Feeders and bird baths can be a focal point in a back yard, notes Habler, who offers overnight rentals of bird videos with such tempting titles as "Cardinals Up Close."

For the serious hobbyist, the bird boutiques sell up to a dozen varieties and combinations of bird seed. A customer also can buy suet -- plain or fancy (the latter appetizingly studded with dehydrated insects, peanuts or raisins).

Judith Juers, a serious bird feeder and Audubon member who lives in Highland Park, Ill., has several squirrel-proof feeders designed with counterweights that cause the opening to the seed bin to close if a squirrel lands on the feeder. Her most recent purchase was a suet feeder, a wire cage that holds suet for birds but protects the cake from marauding squirrels.

Until these specialty stores opened, Juers says, the only way to get information about feeding birds was by trial and error.

"These stores are providing a service that you can't get anywhere else," says Juers, who has been feeding birds for 20 years. "They are convenient, and the shopkeepers are birders themselves who can give good advice."

Juers, who has nine bird feeders in her yard and feeds year-round, spends between $500 and $600 annually for 1,600 pounds of bird seed. During winter, she checks her feeders three times a day and makes sure the heater is working in the water bowl. And she swears by the help she gets from the owners of a bird specialty store.

Bird accessory retailers say they are filling a niche once dominated only by specialty mail-order houses, such as the Northbrook, Ill.-based Audubon Workshop, which has no connection to the Audubon Society. Audubon Workshop owner Al Nelson sold bird merchandise by mail order for more than two decades before he opened a retail store in recent years.

"We feel that we are in the bird information business as much as in the business of selling products," Nelson says.

He can tell you that finches, for example, flock to thistle seeds, blue jays to peanuts and cardinals to sunflower and safflower seeds.

Most birds tend to favor blackoil sunflower seeds. But just to make sure of that, the Cornell Laboratory of Ornithology in Ithaca, N.Y., has asked volunteers this winter to conduct the first-known national taste test of bird seed. Nearly 8,000 amateur bird fanciers in the U.S. and Canada are testing seed varieties. Results are expected next summer. In addition, they are faithfully participating in a second study that records the species and number of birds attracted to feeders.

Project Feederwatch was born seven years ago, and the number of volunteer bird-feeder watchers has quadrupled since then.

Biologists at the Cornell lab now have valuable information about birds' feeding habits and range of habitat, says Margaret Barker, education coordinator for the lab. The lab conducts its feeder survey every winter, from November to April.

Along with the new market growing up around the hobby, there's a certain amount of disinformation about bird habits.

Contrary to popular opinion, feeding birds will not disrupt migratory patterns and tempt warm-weather birds to stay too long in the north and freeze to death.

Birds tend to go where they are supposed to be, says Steve Lewis of U.S. Fish and Wildlife Service, regardless of whether millions of Americans put out tasty treats.